The FRACTRAN program, as described in HSCTF 2014.

Fractran.py

# FRACTRAN - jzhu98
# See bottom for license.

from fractions import Fraction

# Input FRACTRAN code here
code = "455/33,11/13,1/11,3/7,11/2,1/3"

def parse_input(string):
    """Return a list of fractions from the code."""
    string.replace(' ', '')
    fracs = []
    for f in string.split(","):
        fracs.append(Fraction(f))
    return fracs


def fractran(fracs):
    """Run the FRACTRAN code."""
    num = int(input("Input integer: "))
    makes_int = True
    while makes_int:
        makes_int = False
        for f in fracs:
            if num % f.denominator == 0:
                makes_int = True
                num *= f;
                break
    return num

print(fractran(parse_input(code)))

# The MIT License (MIT)
# Copyright (c) 2014 James Zhu
#
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
# in the Software without restriction, including without limitation the rights
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included in all
# copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
# SOFTWARE.